<p>Immunohistochemistry for amyloid-β peptide is a valuable method for Alzheimer’s disease research. Despite a wide variety of available antibodies against the peptides, the difference of immunohistochemical reactivity is not fully described among them. Immunohistochemical reactivity of amyloid-β antibodies is critical for accurate and reliable evaluation of amyloid-β burden in patients as well as models of Alzheimer’s disease. Here, we examined immunohistochemical reactivity of two mouse and one rabbit monoclonal antibodies against the N-terminal region of amyloid-β peptides using two Alzheimer’s disease mouse models, <i>App</i>^{<i>NL−F</i>} and <i>App</i>^{<i>NL−G−F</i>}. 6E10, 82E1 and D54D2 Aβ antibodies were used. We found significant differences in the　immunohistochemical reactivity in both <i>App</i>^{<i>NL−F</i>} and <i>App</i>^{<i>NL−G−F</i>} models. While 6E10 immunoreactivity was mainly localized to amyloid-β plaques, D54D2 and 82E1 antibodies stained much more broadly beyond plaques. Interestingly, the latter two antibodies showed blurred filamentous immunoreactivity beyond plaque cores. Double immunostaining using a tyramide signal amplification method, Fluorochromized Tyramide-Glucose Oxidase, suggested that the differential immunohistochemical outcomes were only partially attributable to their sensitivity. Moreover, heat induced epitope retrieval did not affect the differential immunohistochemical outcomes. Our analysis indicates that outcomes of amyloid-β immunohistochemistry are highly contingent on the antibody used in the study.</p>